Cooling systems suitable for operation with a two-phase refrigerant are known from DE 10 2006 005 035 B3 and DE 10 2009 011 797 A1 and are used for example to cool food which is stored on hoard a passenger aircraft and intended to be distributed to the passengers. Typically, the food intended for supplying to the passengers is kept in mobile transport containers. These transport containers are filled and precooled outside the aircraft and after loading into the aircraft are placed at appropriate locations in the aircraft passenger cabin, for example in the galleys. In order to guarantee that the food remains fresh up to being distributed to the passengers, in the region of the transport container locations cooling stations are provided, which are supplied with cooling energy from a central refrigerating device and release this cooling energy to the transport containers, in which the food is stored.
A cooling system with a central refrigerating device, as opposed to refrigerating units formed separately at the individual transport container locations, has the advantages of a smaller installation volume and a lower weight and moreover entails less outlay for assembly and maintenance. Furthermore, by using a cooling system with a central refrigerating device arranged outside the passenger cabin it is possible to avoid machine noises generated by refrigerating units placed in the region of the transport container locations, which noises are audible in the aircraft passenger cabin and hence may be found to be disturbing.
In the cooling systems known from DE 10 2006 005 035 B3 and DE 10 2009 011 797 A1, the phase transitions of the refrigerant flowing through the cooling circuit of the cooling systems which occur during operation of the system allow the latent heat consumption which then occurs to be utilised for cooling purposes. The refrigerant mass flow needed to provide a desired cooling capacity is therefore markedly lower than for example in a liquid cooling system, in which a one-phase liquid refrigerant is used. Consequently, the cooling systems described in DE 10 2006 005 035 B3 and DE 10 2009 011 797 A1 may have lower line cross sections than a liquid cooling system with a comparable cooling capacity. What is more, the reduction of the refrigerant mass flow makes it possible to reduce the conveying capacity needed to convey the refrigerant through the cooling circuit of the cooling system. This leads to an increased efficiency of the system because less energy is needed to operate a corresponding conveying device, such as for example a pump, and moreover less additional heat generated by the conveying device during operation of the conveying device has to be removed from the cooling system.
In the cooling systems known from the prior art, there is the problem that it is frequently difficult to accommodate the system components in the very limited installation space available on board an aircraft or even position them relative to one another such that, for example, efficiency-optimised operation of the cooling system is made possible by utilising gravity in the process management.